Is there any practical advantage to installing a connectx3 card on a router?

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New Member
May 25, 2021
I have a supermicro X10SLH with 6x10G RJ45s currently running pfsense as my home/lab router. Soon I will be reinstalling router with OPNsense, so it is a good time to go ahead and populate the router's single PCIe slot with additional interface(s). At the same time, I am also finally adding a 48x10G SFP+/4x40G QSFP managed switch to the setup. Current intention is that each server will have a dual port connectX3 card and connect to QSFP on new switch instead of current direct 10G RJ45 connection to router. Current intention is that each server will continue to have it's own subnet for itself and all its VMs/etc.

The router has an available PCIEx8 slot and I have an extra dual port connectX3 card plus DAC cables. And I have a single 10Gb RJ45 SFP+ transceiver, due to the expense, I'm trying to avoid using more than a single 10G RJ45 transceiver (a used connectX3 card plus a cheap DAC cable is literally on par or cheaper than a single 10G RJ45 sfp+ TxR...).

Is there any practical advantage to installing a connectX3 card in my router and using that interface as a vlan trunk (I'm obviously new to this, so please correct me where applicable) to connect new 10/40G switch ? Or should I just use my 10G RJ45 sfp+ transceiver on switch to connect to an available onboard 10G RJ45 port on my router? I have to ask since due to my setup, adding the card will be a PITA, but now's the time to do it if at all.

Your thoughts are much appreciated.